1. Field of the Invention
One or more embodiments of the invention relate to compositions and methods for preparing mesoporous zeolites from low Si/Al zeolites. More particularly, embodiments described herein relate to the preparation of mesoporous zeolites via a framework modification step followed by a mesopore introduction step.
2. Description of the Related Art
Previously, methods have been described for introducing mesoporosity into zeolites such as, for example, in U.S. Pat. No. 7,589,041. These zeolites, namely CBV 720 provided by Zeolyst International, have a high silicon-to-aluminum ratio (“Si/Al”) and a low framework aluminum content. As previously described, this zeolite can be treated in the presence of a pore forming agent (e.g., a surfactant) at a controlled pH under a set of certain time and temperature conditions to introduce mesoporosity into the zeolite. Thereafter, the mesostructured material can be treated to remove the pore forming agent (e.g., by calcination or chemical extraction). Although advances have been made in the art of introducing mesoporosity into zeolites, improvements are still needed.